When you format a partition using Linux's primary file system, ext2, you have the choice of how many bytes
per inode you want. From the man page:
-i bytes-per-inode
Specify the bytes/inode ratio. mke2fs creates an
inode for every bytes-per-inode bytes of space on
the disk. This value defaults to 4096 bytes.
bytes-per-inode must be at least 1024.
This means that by using a smaller size, you will save disk space but may slow down the system. It is a
space/speed trade off.
This is similar to one of FAT16/FAT32' major differences.